Field of the Invention
The present application relates generally to an x-ray source mounting system, and, more particularly, to an adjustable and ergonomic motorized mounting system for sweeping an x-ray source to acquire an intraoral tomosynthesis dataset.
Description of Related Art
X-ray radiography can be performed by positioning an x-ray source on one side of an object (e.g., a patient) and causing the x-ray source to emit x-rays through the object toward an x-ray detector (e.g., radiographic film, a photostimulable phosphor plate, or a digital detector) located on the other side of the object. The x-ray source and detector remain substantially stationary during the radiography procedure. As the x-rays pass through the object, their energies are absorbed to varying degrees depending on the composition of the object, and x-rays arriving at the detector form a two-dimensional (2D) x-ray image (also known as a radiograph) based on the cumulative absorption through the object. Thus, a single radiograph does not provide sufficient depth information about features within an object. Features often appear to overlap in a conventional radiograph, although the features are separate in the object in three-dimensional (3D) space.
X-ray radiography can also be performed in dentistry, in which case, the object of interest to be imaged may be one or more dental anatomies of a patient. The patient typically sits in a reclinable dental chair, and an intraoral x-ray sensor, which can range in size, for example, from 20 mm×26 mm to 27 mm×37 mm, is placed in the patient's mouth adjacent to the dental anatomy of interest. To facilitate positioning of the x-ray source relative to the patient and the x-ray sensor, the x-ray source can be suspended from a wall-mounted or ceiling-mounted adjustable arm for translation in three-dimensional space (i.e., up, down, forward, backward, left, and right movement). The x-ray source housing can also can be designed to permit rotation of the x-ray source around a vertical axis (i.e., a yaw axis) and pivoting of the x-ray source around a horizontal axis (i.e., a pitch axis). However, dental radiographs are formed from cumulative absorption of X-rays (i.e., through the imaged dental anatomy), and do not provide sufficient depth information about the patient's dental anatomy.
X-ray computed tomography (CT) can provide depth information in a 3D image by rotating an x-ray source and detector 360° around an object. However, x-ray CT machines often are large, specialized equipment that require significant financial investments.
Tomosynthesis is an emerging imaging modality that provides 3D information about an object in the form of two-dimensional tomographic image slices by imaging the object with an x-ray source from multiple perspectives within a limited scan angle. Compared to CT imaging, tomosynthesis exposes patients to a lower x-ray dosage, acquires images faster, and can be less expensive. Tomosynthesis systems are commercially available for mammographic imaging. Tomosynthesis as an imaging modality can also be applied to intraoral imaging.
Although conventional dental radiography x-ray sources generally can be adjusted around a yaw axis and a pitch axis, they generally do not have the capability of being scanned through a limited scan angle so as to image an object from multiple perspectives for tomosynthesis imaging.